Monochrome

Multiple examples of monochrome artworks throughout history: an Ancient Egyptian faience statuette of Isis and Horus, 332–30 BC; a gold Tairona pendant, 10th–16th century; a Chinese carved red lacquer, late 14th century; and the Neoclassical Petit Trianon in Versailles, France, by Ange-Jacques Gabriel, 1764
Black-and-white monochrome: the Eiffel Tower during the 1889 Exposition Universelle
Color monochrome: night-vision devices usually produce monochrome images, typically in shades of green.
A photograph of a macaw rendered with a monochrome palette of a limited number of shades
A Philips branded digital audio player with a monochrome display and green backlight, common on older devices including mobile phones and handheld game systems

A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochromatic light refers to electromagnetic radiation that contains a narrow band of wavelengths, which is a distinct concept.